In 2012 the ATLAS and CMS collaborations have discovered a new particle that – within current theoretical and experimental uncertainties – is consistent with the predictions of a Standard-Model (SM) Higgs boson at a mass of \(\sim 125 \,\, \mathrm {GeV}\)  [1]}, [2]}. No conclusive signs of physics beyond the SM have been found so far at the LHC. However, the measurements of Higgs-boson couplings, which are known experimentally to a precision of roughly \(\sim 20\%\) , leave room for Beyond Standard-Model (BSM) interpretations. Consequently, one of the main tasks of the LHC Run 3 and the high-luminosity LHC (HL-LHC) will be to determine the Higgs-boson coupling structures and quantum numbers with highest precision.
